Making Different Decisions: Demonstrating the Influence of Climate Model Uncertainty on Adaptation Pathways

The total global economic cost of flood damages between 1990 and 2024 exceeds £790 billion, with over half of these losses attributed to flood damages occurring in the last decade alone. Recent severe flood events have prompted a shift in flood risk management towards probabilistic approaches, leading to the notion that flood risk management is a continuous process of adaptive management. While substantial research has been dedicated towards characterising and quantifying climate model uncertainty, less focus has been directed towards the propagation of this uncertainty into hydraulically modelled systems and adaptive decision making. Recently, the concept of adaptation pathways has gained growing interest as a decision-focused, analytical tool to assess climate adaptation scenarios under uncertainty. This research develops an approach to quantify climate model uncertainty across multiple plausible adaptation scenarios and examines its influence on adaptation pathways using the case study area of Inverurie, Scotland. Uncertainty is quantified using stratified sampling and captured across scenarios, resulting in the identification and development of adaptation pathways within the context of specified flood risk management objectives and identified adaptation tipping points. The findings underscore the critical importance of embracing uncertainty in adaptation pathways to support robust, informed decision making.